Bug 1085212: release video hardware before sharing and restore when done

Followup fix for bug 1088456: use playerShowing instead of playing so the patch works even if we are paused
You're right. I remembered to add that in the 2.0 patch, but didn't come back here and add it.  Since this is only ever called when an activity is launched, I don't believe that any bug is actually possible, but I should add it.